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<FONT color="green">001</FONT>    /*<a name="line.1"></a>
<FONT color="green">002</FONT>     * Licensed to the Apache Software Foundation (ASF) under one or more<a name="line.2"></a>
<FONT color="green">003</FONT>     * contributor license agreements.  See the NOTICE file distributed with<a name="line.3"></a>
<FONT color="green">004</FONT>     * this work for additional information regarding copyright ownership.<a name="line.4"></a>
<FONT color="green">005</FONT>     * The ASF licenses this file to You under the Apache License, Version 2.0<a name="line.5"></a>
<FONT color="green">006</FONT>     * (the "License"); you may not use this file except in compliance with<a name="line.6"></a>
<FONT color="green">007</FONT>     * the License.  You may obtain a copy of the License at<a name="line.7"></a>
<FONT color="green">008</FONT>     *<a name="line.8"></a>
<FONT color="green">009</FONT>     *     http://www.apache.org/licenses/LICENSE-2.0<a name="line.9"></a>
<FONT color="green">010</FONT>     *<a name="line.10"></a>
<FONT color="green">011</FONT>     * Unless required by applicable law or agreed to in writing, software<a name="line.11"></a>
<FONT color="green">012</FONT>     * distributed under the License is distributed on an "AS IS" BASIS,<a name="line.12"></a>
<FONT color="green">013</FONT>     * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.<a name="line.13"></a>
<FONT color="green">014</FONT>     * See the License for the specific language governing permissions and<a name="line.14"></a>
<FONT color="green">015</FONT>     * limitations under the License.<a name="line.15"></a>
<FONT color="green">016</FONT>     */<a name="line.16"></a>
<FONT color="green">017</FONT>    package org.apache.commons.jxpath.ri.compiler;<a name="line.17"></a>
<FONT color="green">018</FONT>    <a name="line.18"></a>
<FONT color="green">019</FONT>    import java.util.Collection;<a name="line.19"></a>
<FONT color="green">020</FONT>    import java.util.HashSet;<a name="line.20"></a>
<FONT color="green">021</FONT>    import java.util.Iterator;<a name="line.21"></a>
<FONT color="green">022</FONT>    <a name="line.22"></a>
<FONT color="green">023</FONT>    import org.apache.commons.jxpath.ri.EvalContext;<a name="line.23"></a>
<FONT color="green">024</FONT>    import org.apache.commons.jxpath.ri.InfoSetUtil;<a name="line.24"></a>
<FONT color="green">025</FONT>    import org.apache.commons.jxpath.ri.axes.InitialContext;<a name="line.25"></a>
<FONT color="green">026</FONT>    import org.apache.commons.jxpath.ri.axes.SelfContext;<a name="line.26"></a>
<FONT color="green">027</FONT>    <a name="line.27"></a>
<FONT color="green">028</FONT>    /**<a name="line.28"></a>
<FONT color="green">029</FONT>     * Base implementation of Expression for the operations "&amp;gt;", "&amp;gt;=", "&amp;lt;", "&amp;lt;=".<a name="line.29"></a>
<FONT color="green">030</FONT>     * @since JXPath 1.3<a name="line.30"></a>
<FONT color="green">031</FONT>     *<a name="line.31"></a>
<FONT color="green">032</FONT>     * @author Matt Benson<a name="line.32"></a>
<FONT color="green">033</FONT>     * @version $Revision: 652845 $ $Date: 2008-05-02 12:46:46 -0500 (Fri, 02 May 2008) $<a name="line.33"></a>
<FONT color="green">034</FONT>     */<a name="line.34"></a>
<FONT color="green">035</FONT>    public abstract class CoreOperationRelationalExpression extends CoreOperation {<a name="line.35"></a>
<FONT color="green">036</FONT>    <a name="line.36"></a>
<FONT color="green">037</FONT>        /**<a name="line.37"></a>
<FONT color="green">038</FONT>         * Create a new CoreOperationRelationalExpression.<a name="line.38"></a>
<FONT color="green">039</FONT>         * @param args arguments<a name="line.39"></a>
<FONT color="green">040</FONT>         */<a name="line.40"></a>
<FONT color="green">041</FONT>        protected CoreOperationRelationalExpression(Expression[] args) {<a name="line.41"></a>
<FONT color="green">042</FONT>            super(args);<a name="line.42"></a>
<FONT color="green">043</FONT>        }<a name="line.43"></a>
<FONT color="green">044</FONT>    <a name="line.44"></a>
<FONT color="green">045</FONT>        public final Object computeValue(EvalContext context) {<a name="line.45"></a>
<FONT color="green">046</FONT>            return compute(args[0].compute(context), args[1].compute(context))<a name="line.46"></a>
<FONT color="green">047</FONT>                    ? Boolean.TRUE : Boolean.FALSE;<a name="line.47"></a>
<FONT color="green">048</FONT>        }<a name="line.48"></a>
<FONT color="green">049</FONT>    <a name="line.49"></a>
<FONT color="green">050</FONT>        protected final int getPrecedence() {<a name="line.50"></a>
<FONT color="green">051</FONT>            return RELATIONAL_EXPR_PRECEDENCE;<a name="line.51"></a>
<FONT color="green">052</FONT>        }<a name="line.52"></a>
<FONT color="green">053</FONT>    <a name="line.53"></a>
<FONT color="green">054</FONT>        protected final boolean isSymmetric() {<a name="line.54"></a>
<FONT color="green">055</FONT>            return false;<a name="line.55"></a>
<FONT color="green">056</FONT>        }<a name="line.56"></a>
<FONT color="green">057</FONT>    <a name="line.57"></a>
<FONT color="green">058</FONT>        /**<a name="line.58"></a>
<FONT color="green">059</FONT>         * Template method for subclasses to evaluate the result of a comparison.<a name="line.59"></a>
<FONT color="green">060</FONT>         * @param compare result of comparison to evaluate<a name="line.60"></a>
<FONT color="green">061</FONT>         * @return ultimate operation success/failure<a name="line.61"></a>
<FONT color="green">062</FONT>         */<a name="line.62"></a>
<FONT color="green">063</FONT>        protected abstract boolean evaluateCompare(int compare);<a name="line.63"></a>
<FONT color="green">064</FONT>    <a name="line.64"></a>
<FONT color="green">065</FONT>        /**<a name="line.65"></a>
<FONT color="green">066</FONT>         * Compare left to right.<a name="line.66"></a>
<FONT color="green">067</FONT>         * @param left left operand<a name="line.67"></a>
<FONT color="green">068</FONT>         * @param right right operand<a name="line.68"></a>
<FONT color="green">069</FONT>         * @return operation success/failure<a name="line.69"></a>
<FONT color="green">070</FONT>         */<a name="line.70"></a>
<FONT color="green">071</FONT>        private boolean compute(Object left, Object right) {<a name="line.71"></a>
<FONT color="green">072</FONT>            left = reduce(left);<a name="line.72"></a>
<FONT color="green">073</FONT>            right = reduce(right);<a name="line.73"></a>
<FONT color="green">074</FONT>    <a name="line.74"></a>
<FONT color="green">075</FONT>            if (left instanceof InitialContext) {<a name="line.75"></a>
<FONT color="green">076</FONT>                ((InitialContext) left).reset();<a name="line.76"></a>
<FONT color="green">077</FONT>            }<a name="line.77"></a>
<FONT color="green">078</FONT>            if (right instanceof InitialContext) {<a name="line.78"></a>
<FONT color="green">079</FONT>                ((InitialContext) right).reset();<a name="line.79"></a>
<FONT color="green">080</FONT>            }<a name="line.80"></a>
<FONT color="green">081</FONT>            if (left instanceof Iterator &amp;&amp; right instanceof Iterator) {<a name="line.81"></a>
<FONT color="green">082</FONT>                return findMatch((Iterator) left, (Iterator) right);<a name="line.82"></a>
<FONT color="green">083</FONT>            }<a name="line.83"></a>
<FONT color="green">084</FONT>            if (left instanceof Iterator) {<a name="line.84"></a>
<FONT color="green">085</FONT>                return containsMatch((Iterator) left, right);<a name="line.85"></a>
<FONT color="green">086</FONT>            }<a name="line.86"></a>
<FONT color="green">087</FONT>            if (right instanceof Iterator) {<a name="line.87"></a>
<FONT color="green">088</FONT>                return containsMatch((Iterator) right, left);<a name="line.88"></a>
<FONT color="green">089</FONT>            }<a name="line.89"></a>
<FONT color="green">090</FONT>            double ld = InfoSetUtil.doubleValue(left);<a name="line.90"></a>
<FONT color="green">091</FONT>            if (Double.isNaN(ld)) {<a name="line.91"></a>
<FONT color="green">092</FONT>                return false;<a name="line.92"></a>
<FONT color="green">093</FONT>            }<a name="line.93"></a>
<FONT color="green">094</FONT>            double rd = InfoSetUtil.doubleValue(right);<a name="line.94"></a>
<FONT color="green">095</FONT>            if (Double.isNaN(rd)) {<a name="line.95"></a>
<FONT color="green">096</FONT>                return false;<a name="line.96"></a>
<FONT color="green">097</FONT>            }<a name="line.97"></a>
<FONT color="green">098</FONT>            return evaluateCompare(ld == rd ? 0 : ld &lt; rd ? -1 : 1);<a name="line.98"></a>
<FONT color="green">099</FONT>        }<a name="line.99"></a>
<FONT color="green">100</FONT>    <a name="line.100"></a>
<FONT color="green">101</FONT>        /**<a name="line.101"></a>
<FONT color="green">102</FONT>         * Reduce an operand for comparison.<a name="line.102"></a>
<FONT color="green">103</FONT>         * @param o Object to reduce<a name="line.103"></a>
<FONT color="green">104</FONT>         * @return reduced operand<a name="line.104"></a>
<FONT color="green">105</FONT>         */<a name="line.105"></a>
<FONT color="green">106</FONT>        private Object reduce(Object o) {<a name="line.106"></a>
<FONT color="green">107</FONT>            if (o instanceof SelfContext) {<a name="line.107"></a>
<FONT color="green">108</FONT>                o = ((EvalContext) o).getSingleNodePointer();<a name="line.108"></a>
<FONT color="green">109</FONT>            }<a name="line.109"></a>
<FONT color="green">110</FONT>            if (o instanceof Collection) {<a name="line.110"></a>
<FONT color="green">111</FONT>                o = ((Collection) o).iterator();<a name="line.111"></a>
<FONT color="green">112</FONT>            }<a name="line.112"></a>
<FONT color="green">113</FONT>            return o;<a name="line.113"></a>
<FONT color="green">114</FONT>        }<a name="line.114"></a>
<FONT color="green">115</FONT>    <a name="line.115"></a>
<FONT color="green">116</FONT>        /**<a name="line.116"></a>
<FONT color="green">117</FONT>         * Learn whether any element returned from an Iterator matches a given value.<a name="line.117"></a>
<FONT color="green">118</FONT>         * @param it Iterator<a name="line.118"></a>
<FONT color="green">119</FONT>         * @param value to look for<a name="line.119"></a>
<FONT color="green">120</FONT>         * @return whether a match was found<a name="line.120"></a>
<FONT color="green">121</FONT>         */<a name="line.121"></a>
<FONT color="green">122</FONT>        private boolean containsMatch(Iterator it, Object value) {<a name="line.122"></a>
<FONT color="green">123</FONT>            while (it.hasNext()) {<a name="line.123"></a>
<FONT color="green">124</FONT>                Object element = it.next();<a name="line.124"></a>
<FONT color="green">125</FONT>                if (compute(element, value)) {<a name="line.125"></a>
<FONT color="green">126</FONT>                    return true;<a name="line.126"></a>
<FONT color="green">127</FONT>                }<a name="line.127"></a>
<FONT color="green">128</FONT>            }<a name="line.128"></a>
<FONT color="green">129</FONT>            return false;<a name="line.129"></a>
<FONT color="green">130</FONT>        }<a name="line.130"></a>
<FONT color="green">131</FONT>    <a name="line.131"></a>
<FONT color="green">132</FONT>        /**<a name="line.132"></a>
<FONT color="green">133</FONT>         * Learn whether there is an intersection between two Iterators.<a name="line.133"></a>
<FONT color="green">134</FONT>         * @param lit left Iterator<a name="line.134"></a>
<FONT color="green">135</FONT>         * @param rit right Iterator<a name="line.135"></a>
<FONT color="green">136</FONT>         * @return whether a match was found<a name="line.136"></a>
<FONT color="green">137</FONT>         */<a name="line.137"></a>
<FONT color="green">138</FONT>        private boolean findMatch(Iterator lit, Iterator rit) {<a name="line.138"></a>
<FONT color="green">139</FONT>            HashSet left = new HashSet();<a name="line.139"></a>
<FONT color="green">140</FONT>            while (lit.hasNext()) {<a name="line.140"></a>
<FONT color="green">141</FONT>                left.add(lit.next());<a name="line.141"></a>
<FONT color="green">142</FONT>            }<a name="line.142"></a>
<FONT color="green">143</FONT>            while (rit.hasNext()) {<a name="line.143"></a>
<FONT color="green">144</FONT>                if (containsMatch(left.iterator(), rit.next())) {<a name="line.144"></a>
<FONT color="green">145</FONT>                    return true;<a name="line.145"></a>
<FONT color="green">146</FONT>                }<a name="line.146"></a>
<FONT color="green">147</FONT>            }<a name="line.147"></a>
<FONT color="green">148</FONT>            return false;<a name="line.148"></a>
<FONT color="green">149</FONT>        }<a name="line.149"></a>
<FONT color="green">150</FONT>    <a name="line.150"></a>
<FONT color="green">151</FONT>    }<a name="line.151"></a>




























































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